A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Carat weight measures weight, not size. A diamond carat size chart shows approximate millimeter dimensions by shape. For example, a 1 carat round is about 6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm. Always check actual mm measurements when comparing diamonds — carat alone does not tell you how large a diamond will look.
Diamond size varies significantly by shape at the same carat weight. Always compare mm measurements.
Diamond Carat Size Chart by Shape
カラット
Round (mm)
Oval (mm)
Cushion (mm)
Emerald (mm)
Princess (mm)
0.50
5.2
6.0 × 4.4
4.4 × 4.0
5.0 × 3.5
4.4 × 4.4
0.75
5.9
6.8 × 5.0
5.0 × 4.5
5.8 × 4.0
5.0 × 5.0
1.00
6.5
7.5 × 5.5
5.5 × 5.0
6.5 × 4.5
5.5 × 5.5
1.25
6.9
8.0 × 5.9
5.9 × 5.4
6.9 × 4.9
5.9 × 5.9
1.50
7.3
8.6 × 6.4
6.3 × 5.7
7.5 × 5.3
6.3 × 6.3
2.00
8.1
9.5 × 7.0
7.0 × 6.3
8.3 × 5.9
7.0 × 7.0
2.50
8.7
10.2 × 7.5
7.5 × 6.8
8.9 × 6.3
7.5 × 7.5
3.00
9.3
11.0 × 8.0
8.0 × 7.3
9.4 × 6.7
8.0 × 8.0
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
This guide provides approximate millimeter measurements for the most popular diamond shapes at common carat weights.
Quick Answer:
Carat weight measures weight, not size. A diamond carat size chart shows approximate millimeter dimensions by shape. For example, a 1 carat round is about 6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm. Always check actual mm measurements when comparing diamonds — carat alone does not tell you how large a diamond will look.
Diamond size varies significantly by shape at the same carat weight. Always compare mm measurements.
Diamond Carat Size Chart by Shape
カラット
Round (mm)
Oval (mm)
Cushion (mm)
Emerald (mm)
Princess (mm)
0.50
5.2
6.0 × 4.4
4.4 × 4.0
5.0 × 3.5
4.4 × 4.4
0.75
5.9
6.8 × 5.0
5.0 × 4.5
5.8 × 4.0
5.0 × 5.0
1.00
6.5
7.5 × 5.5
5.5 × 5.0
6.5 × 4.5
5.5 × 5.5
1.25
6.9
8.0 × 5.9
5.9 × 5.4
6.9 × 4.9
5.9 × 5.9
1.50
7.3
8.6 × 6.4
6.3 × 5.7
7.5 × 5.3
6.3 × 6.3
2.00
8.1
9.5 × 7.0
7.0 × 6.3
8.3 × 5.9
7.0 × 7.0
2.50
8.7
10.2 × 7.5
7.5 × 6.8
8.9 × 6.3
7.5 × 7.5
3.00
9.3
11.0 × 8.0
8.0 × 7.3
9.4 × 6.7
8.0 × 8.0
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Diamond size is measured in millimeters, not just carats. Two diamonds of the same carat weight can have completely different dimensions depending on their shape and cut proportions. A carat size chart helps you compare actual face-up sizes across shapes so you can make an informed decision.
This guide provides approximate millimeter measurements for the most popular diamond shapes at common carat weights.
Quick Answer:
Carat weight measures weight, not size. A diamond carat size chart shows approximate millimeter dimensions by shape. For example, a 1 carat round is about 6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm. Always check actual mm measurements when comparing diamonds — carat alone does not tell you how large a diamond will look.
Diamond size varies significantly by shape at the same carat weight. Always compare mm measurements.
Diamond Carat Size Chart by Shape
カラット
Round (mm)
Oval (mm)
Cushion (mm)
Emerald (mm)
Princess (mm)
0.50
5.2
6.0 × 4.4
4.4 × 4.0
5.0 × 3.5
4.4 × 4.4
0.75
5.9
6.8 × 5.0
5.0 × 4.5
5.8 × 4.0
5.0 × 5.0
1.00
6.5
7.5 × 5.5
5.5 × 5.0
6.5 × 4.5
5.5 × 5.5
1.25
6.9
8.0 × 5.9
5.9 × 5.4
6.9 × 4.9
5.9 × 5.9
1.50
7.3
8.6 × 6.4
6.3 × 5.7
7.5 × 5.3
6.3 × 6.3
2.00
8.1
9.5 × 7.0
7.0 × 6.3
8.3 × 5.9
7.0 × 7.0
2.50
8.7
10.2 × 7.5
7.5 × 6.8
8.9 × 6.3
7.5 × 7.5
3.00
9.3
11.0 × 8.0
8.0 × 7.3
9.4 × 6.7
8.0 × 8.0
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Diamond size is measured in millimeters, not just carats. Two diamonds of the same carat weight can have completely different dimensions depending on their shape and cut proportions. A carat size chart helps you compare actual face-up sizes across shapes so you can make an informed decision.
This guide provides approximate millimeter measurements for the most popular diamond shapes at common carat weights.
Quick Answer:
Carat weight measures weight, not size. A diamond carat size chart shows approximate millimeter dimensions by shape. For example, a 1 carat round is about 6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm. Always check actual mm measurements when comparing diamonds — carat alone does not tell you how large a diamond will look.
Diamond size varies significantly by shape at the same carat weight. Always compare mm measurements.
Diamond Carat Size Chart by Shape
カラット
Round (mm)
Oval (mm)
Cushion (mm)
Emerald (mm)
Princess (mm)
0.50
5.2
6.0 × 4.4
4.4 × 4.0
5.0 × 3.5
4.4 × 4.4
0.75
5.9
6.8 × 5.0
5.0 × 4.5
5.8 × 4.0
5.0 × 5.0
1.00
6.5
7.5 × 5.5
5.5 × 5.0
6.5 × 4.5
5.5 × 5.5
1.25
6.9
8.0 × 5.9
5.9 × 5.4
6.9 × 4.9
5.9 × 5.9
1.50
7.3
8.6 × 6.4
6.3 × 5.7
7.5 × 5.3
6.3 × 6.3
2.00
8.1
9.5 × 7.0
7.0 × 6.3
8.3 × 5.9
7.0 × 7.0
2.50
8.7
10.2 × 7.5
7.5 × 6.8
8.9 × 6.3
7.5 × 7.5
3.00
9.3
11.0 × 8.0
8.0 × 7.3
9.4 × 6.7
8.0 × 8.0
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
Diamond size is measured in millimeters, not just carats. Two diamonds of the same carat weight can have completely different dimensions depending on their shape and cut proportions. A carat size chart helps you compare actual face-up sizes across shapes so you can make an informed decision.
This guide provides approximate millimeter measurements for the most popular diamond shapes at common carat weights.
Quick Answer:
Carat weight measures weight, not size. A diamond carat size chart shows approximate millimeter dimensions by shape. For example, a 1 carat round is about 6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm. Always check actual mm measurements when comparing diamonds — carat alone does not tell you how large a diamond will look.
Diamond size varies significantly by shape at the same carat weight. Always compare mm measurements.
Diamond Carat Size Chart by Shape
カラット
Round (mm)
Oval (mm)
Cushion (mm)
Emerald (mm)
Princess (mm)
0.50
5.2
6.0 × 4.4
4.4 × 4.0
5.0 × 3.5
4.4 × 4.4
0.75
5.9
6.8 × 5.0
5.0 × 4.5
5.8 × 4.0
5.0 × 5.0
1.00
6.5
7.5 × 5.5
5.5 × 5.0
6.5 × 4.5
5.5 × 5.5
1.25
6.9
8.0 × 5.9
5.9 × 5.4
6.9 × 4.9
5.9 × 5.9
1.50
7.3
8.6 × 6.4
6.3 × 5.7
7.5 × 5.3
6.3 × 6.3
2.00
8.1
9.5 × 7.0
7.0 × 6.3
8.3 × 5.9
7.0 × 7.0
2.50
8.7
10.2 × 7.5
7.5 × 6.8
8.9 × 6.3
7.5 × 7.5
3.00
9.3
11.0 × 8.0
8.0 × 7.3
9.4 × 6.7
8.0 × 8.0
These measurements are approximate and vary based on cut quality, depth percentage, and individual proportions. Always check the actual dimensions listed on a diamond’s certificate. Learn more about diamond measurements.
Carat weight and millimeter size do not always align. Check actual dimensions before comparing diamonds.
How to Use This Chart
The chart above shows approximate millimeter sizes for well-cut diamonds. Use it as a starting point when comparing diamonds of different shapes and carat weights. For example, if you are choosing between a 1 carat round (6.5 mm) and a 0.75 carat oval (6.8 × 5.0 mm), the oval may appear longer even though it weighs less.
Remember that elongated shapes like oval, pear, and marquise create more finger coverage per carat than round or cushion shapes. Use the chart to compare actual dimensions rather than relying on carat weight alone.
Use a carat size chart to compare actual millimeter dimensions across shapes before making your decision.
Quick Reference
To maximize visible size per carat: choose oval, pear, or marquise.
For a balanced, classic look: choose round or cushion.
Always check: length and width in millimeters on the certificate.
Remember: a well-cut 0.90 carat diamond can look as large as a poorly-cut 1.00 carat.
Comparing diamonds only by carat weight without checking mm measurements.
Assuming a 1 carat diamond always measures 6.5 mm — this is only true for round brilliants.
Ignoring depth percentage — a deep diamond may face up smaller than its carat suggests.
Using generic size charts without verifying individual stone measurements.
Myth vs Fact
Myth
Fact
All 1 carat diamonds are the same size.
A 1 carat round is ~6.5 mm, while a 1 carat oval can be 7.5 × 5.5 mm — different dimensions.
Carat weight tells you the physical size.
Carat is weight, not size. Millimeter measurements tell you the physical dimensions.
Two diamonds with the same mm size always weigh the same.
Cut depth affects weight — two 6.5 mm diamonds can have different carat weights.
よくある質問
How many mm is a 1 carat diamond?
A 1 carat round brilliant diamond is about 6.5 mm in diameter. Other shapes have different dimensions.
What is the mm size of a 2 carat diamond?
A 2 carat round brilliant is about 8.1 mm in diameter. A 2 carat oval is about 9.5 × 7.0 mm.
Which shape looks biggest at the same carat weight?
Marquise, oval, and pear diamonds look largest because their elongated shapes create more finger coverage per carat.
Does a deeper diamond look smaller?
Yes, a deeper diamond hides more weight below the girdle and faces up smaller than a shallower diamond of the same carat.
Can a 0.90 carat look as big as a 1.00 carat?
Yes, a well-cut 0.90 carat diamond with ideal proportions can face up similarly to a 1.00 carat with a deep cut.
Final Buying Note
A diamond carat size chart is a useful tool, but it is only a starting point. The actual millimeter measurements of each diamond you consider are more important than the carat weight. Compare shapes, check dimensions, and choose the diamond that looks best on your finger — not just the one with the highest carat number.
